Tamiya 70093 3-Speed Crank-Axle Gearbox Kit

Tamiya’s 3-speed crank-axle gearbox looks very much like half of the twin-motor gearbox (with an added gear ratio option). This compact gearbox can be built in one of three gear ratios (17:1, 58:1, and 204:1), and is Tamiya’s cheapest, general-purpose gearbox.

Adam, who posts under the username nexisnet on the Pololu forums, has performed a detailed series of experiments to determine how operating voltage affects the lifetime of the Mabuchi FA-130 motor, which happens to be the motors used in the Tamiya 70168 Double Gearbox, 70167 Single Gearbox (4-Speed), 70097 Twin-Motor Gearbox, 70093 3-Speed Crank-Axle Gearbox, 70110 4-Speed Crank-Axle Gearbox, and 70103 Universal Gearbox.